Device for causing end play of shafts.



Patented Mar. l2, l90l.

A. E. AVERRETT.

DEVICE FOR GAUSING END PLAY 0F S HAFTS.

(Application filed Jan. 27, 1899.

(No Model.)

Oqh dr eW E. J verrefi y fi thy.

UNITED STATES PATENT ANDREl V E. AVERRETT, OF SCHENEC-TADY, NEW YORK, ASSIGNOR. TO THE GENERAL ELECTRIC COMPANY, OF NEV YORK.

DEVICE FOR CAUSING END PLAY @F SHAFTS.

SPECIFICATION forming part of Letters Patent No. 669,612, dated March 12, 1901.

Application filed January 27, 1899. Serial No. 703,587. \NO model.)

T0 at whom, it may concern.-

Be it known that 1, ANDREW E. Avnnnn'r'r,

a citizen of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements in Devices for Causing End Play of Shafts, (Case No. 1,019,) of which the following is a specification.

The present invention relates to the now well-known electromagnetic devices for causing a shaft to reciprocate in its bearings. Its most important application has hitherto been to dynamoelectric machines, and particularly to rotary converters and other commutator-machines, in which the brushes are apt to wear grooves unless they are displaced longitudinally from time to time. In the ordinary dynamo of the belt-driven class the desired reciprocation is effected by variations of belt tension and alinement, so that in general no special devices are necessary; but in a rotary converter and in some kinds of di rest-connected apparatus there is a cen tralizing tendency (more particularly in the converter) which makes the brushes run in the same track around the commutator. The incidental roughness in the commutator-surface tends to make the brushes spark and to destroy the polish of the commutator and the close fit of the brushes necessary to give the best commutation.

Several forms of the electromagnetic device have been arranged by different inventors; and my present invention relates to a simple and efficient mechanical embodiment of the driving mechanism by which the impulses of current are sent through the disk-like electromagnet, which is commonly applied to the end of the shaft near one of the bearings. Most of the old forms of the device rotate the commutator which makes and breaks the circuit of the electromagnet by motors of dif ferent kinds.

It is the object of the present invention to connectthe commutator directly to the shaft of the converter or other dynamo. Inasmuch, however, as this would give very frequent im pulses and as the power of the magnet compared to the weight of the armature and shaft is not very great, I have found it advisable to give the commutator only a comparatively slow motion, so that the periods of magnetization and t'lemagnetization are of comparatively long duration. This I effect in the particular form illustrated by mounting in the center of the magnet in a bearing provided for that purpose a shaft which is driven by a pin from the converter-shaft and which meshes with a fork in the end of the smaller shaft. Upon the other end of the latter a worm is formed and the commutator is driven by the wormwheel.

The accompanying drawings show an embodiment of the invention as applied to a rotary converter.

Figure 1 is a side elevation of a converter to which the invention is applied; and Figs. 2 and 3 are enlarged views showing the details, 2 being partly broken away.

A is the converter, of which A is the armature.

B is the alternatingcurrent-collecting device, and C is the commutator. From the latter the supply-lines a I) lead off, and a shunt across them, including magnet E, is closed from time to time by the commutator device D. The details of the latter are best understood from Figs. 2 and 3. In these, D is a bar of insulating material, which carries pair of brushes d d. One of these is connected to one of the mains a b, and the other to the coil, (see Fig. 3,) one end of which is connected to the other main, and when the commutator, which consists of two cam-like portions F F, connected by an intermediate hub of conducting material F insulated from the shaft carrying the worm-wheel, rotates it bridges the two brushes d d. The terminals of the electromagnet are thus supplied with current, and when the two brushes are bridged an impulse of current passes through the coil E,continuing so long as they are upon the metal face of the commutator. When, however, they snap off the high part of the commutator, as shown in dotted lines in Fig. 2, the circuit is again opened. The commutator F is rotated by the worm-wheel G and this in turn derives its motion from the worm G, mounted on the shaft G, which turns in the bushing g, mounted in the magnet E. A fork G is formed on the end of the shaft, and with this a pin meshes to turn the worm, the

pin being secured in stud H, driven by the end of the converter-shaft. The Whole structure is secured in place by the lugs 6, through which bolts pass to fasten it to the bearingcap in the usual Way.

'What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. A device for causing end play in shafts, comprising an electroniagnet in circuit With a source of current, a make-and-break device in the circuit, a Worm rotated by the shaft, and a worm-wheel operating the make-andbreak device.

2. A device for causing end play in a shaft, coinprisingan electromagnet,acircuit through the magnet-coil from a source of current, a commutator in the circuit,a Worm-wheel driving the commutator, and a worm mounted in the magnet-core and driven by a sliding connection with the shaft.

3. The combination of the ma net, the commutatorand its Worm-\vl1eel,tl1e Worm mounted in the magnet, and the pin and fork forming a sliding connection between the Worm and a shaft to be reeiprocated.

4. A device for causing end play in a shaft, comprising an electromagnet in circuit with a source of current, a make-andbreak device in the circuit, and a second shaft making a sliding connection with the first shaft and communicating motion to the make-and-break device.

5. A device for causing end play in a shaft, comprising an electromaguet in circuit \vilh a source of current, a make-and-break device in the circuit, a secondary shaft arranged coaxially with the first shaft and driven thereby and in operative relation to the make-andbreak device.

6. The combination of two shafts mounted to rotate about the same axial line and relatively movable along said line, and a circuitbrealcing device in operative relation to one of said shafts.

In witness whereof I have hereunto set my hand this 20th day of January, 1899.

ANDREW E. AVERRE'F'F. iVitnesses:

B. B. HULL, M. H. EMERSON. 

